S&W 25-5 cylinder reaming

[Shrek Of The Arctic]

I just picked up a bucket list gun in the form of a S&W Model 25-5. It is exquisite in most every way, except...for the darn oversized cylinder throats. I was able to drop a .458 bullet through some of them...

So...I need a new cylinder fit to it.

Is there any particular size or style I need to consider? I did find that the recessed cylinder from my 28-2 4 screw fit like it was absolutely meant to be there. The cylinder from my 625-9 Mountain Gun fit, but was barely in time and didn't operate smoothly. (Unsurprising for just slapping it in there)

Beyond aesthetics that may or may not be someone's cup of tea, is there any advantage to a stainless cylinder? (Besides not having to get it properly blued) does recessed/non recessed matter? Can an extractor be reamed as well, or do I need to hunt down a .45 Colt specific one?

Finally, this kinda work would be pushing my abilities, and I lack the tools. Anyone that could be recommended to the job?

I've read several folks that have done caliber conversions on these big, lovely N frames. I just wanna verify some specifics before delving too far into the task.

Many thanks for your thoughts and your time!

 

[StrawHat]

Steelslaver will be along to coach you but yes, it can be done.

Smaller cartridge cylinders are available on auction sites. Get one with the extractor. Whoever does the work can ream the extractor at the same time. Drop cartridges in the 5 empty chamber and ream #6. Keep working your way around until all six are done. A good machinist should be capable of this job.

Good luck and keep us posted.

Kevin

 

[Protocall_Design]

A stainless cylinder will be more rustproof, maybe easier to find. Reaming the cylinder is easy with the right reamer. You will want to ream with the extractor in place, as that is part of the chamber. A recessed cylinder or non only matters in terms of the frame lug to hold it in when the cylinder is open. I prefer Manson reamers over Clymer.

 

[steelslaver]

If you put a 28-2 cylinder in a 25-5 you would have a HUGE gap unless you set the barrel back a lot. I use 44 mag cylinders, first reaming them to .452 then running a 45 colt reamer in them. The only problem with using a recessed cylinder in a model 25 is you must file .060 off the face of the frame lug without marring the frame. I protect the frame with a bit of very thin 309 stainless heat treat foil and use a file with no teeth on either of the flats, just the edges. I have some cylinders if you want one.

I use a stub of a extractor rod with a special washer I made to hold the extractor down tight while I ream. Like someone said start with several full chambers, line the empty one up, ream it, fill it with the new case and go to another. If you make a spud that just fits the original chamber it is easy to line each chamber up perfectly then keep the bed locked until that chamber is done.

This is making a K22 cylinder into a 327 mag cylinder
the extractor lock down

The alignment spud Note 3 chambers are already done

I use a 1/4" reamer, then a 19/64" (0.297) reamer to remove the majority of the material

then a 327 finish reamer with a pilot to match the .297 sized reamer

Notice the brass inserts in the machine vice jaws, you must turn the reamers slow, use lots of cutting oil, cut a ways, come out spay reamer and hole with brake cleaner, re oil the reamer and go some more. I probably go in and out at least 6 times with the finish reamer.

For 44mag to 45 colt cylinders, first the spud, then I have a reamer with a 429 pilot that cuts to .452, then I use a 45 colt reamer with a .452 pilot. When I am done each chamber gets a pass with a oiled up ball brush hone.

You also need to clean the front face of the cylinder up with a fine file as the reamer will leave a fine bur of material on the edges of the holes

A pinned and recessed 5 screw 45 colt made from an early highway Patrolman. Bubba had already messed up the original the 357 cylinder

 

[Hair Trigger]

I just picked up a bucket list gun in the form of a S&W Model 25-5. It is exquisite in most every way, except...for the darn oversized cylinder throats. I was able to drop a .458 bullet through some of them...

So...I need a new cylinder fit to it.

Is there any particular size or style I need to consider? I did find that the recessed cylinder from my 28-2 4 screw fit like it was absolutely meant to be there. The cylinder from my 625-9 Mountain Gun fit, but was barely in time and didn't operate smoothly. (Unsurprising for just slapping it in there)

Beyond aesthetics that may or may not be someone's cup of tea, is there any advantage to a stainless cylinder? (Besides not having to get it properly blued) does recessed/non recessed matter? Can an extractor be reamed as well, or do I need to hunt down a .45 Colt specific one?

Finally, this kinda work would be pushing my abilities, and I lack the tools. Anyone that could be recommended to the job?

I've read several folks that have done caliber conversions on these big, lovely N frames. I just wanna verify some specifics before delving too far into the task.

Many thanks for your thoughts and your time!

Have you actually fired this revolver to check its accuracy with the cylinder it came with? You say "it is exquisite in almost every way", and then immediately plan to Frankengun it, which regardless of it becoming more accurate (and that isn't guaranteed) robs a good bit of its value. What year was this one manufactured? Does it still have a pinned barrel?

 

[steelslaver]

It isn't like he has to throw the original cylinder in the garbage. A 25 colt with huge throats is more of a frankengun, than one that is set up with proper throats anyway. The 25-5 guns don't have serial numbered cylinders either BTW. Also, I will bet it is pinned as S&W started making the cylinders with .452 throats when the pin went away.

 

[Shrek Of The Arctic]

I am going to be firing this revolver along side a 625-9 Mountain Gun and a Charter Arms Pitbull chambered in .45 Colt shortly after sunrise this morning. I'll be using 4-5 different loads from 185-255 grain. While I have heard of these 25-5s inexplicably shooting well with oversize cylinder throats, I think the odds do not favor that conclusion.

"Frankengun" it? Cylinders come on and off with the same ease as a set of stocks. The original cylinder will remain unused. It could even be argued that I'm preserving the original mal-formed cylinder by not using it and letting it develop a turn ring.

Beyond that, I could care less about affecting it's collector value. I am a shooter, not a collector. I intend this firearm to be the one I want, not to represent someone else's idea of what's appropriate.

It does have a pinned barrel. If it didn't I likely would not be looking into correcting this matter. SN seems to put it between 1980 and 1983. It's a later number so...likely more 1982-1983 if I were to speculate.

I'd actually love to be proven wrong, but with .458 bullets dropping freely through a couple of the cylinder holes, I think it's quite unlikely.

 

[CH4]

Another vote for shooting different loads through it first. Ya just never know; accuracy may be just fine.

 

[SlamFire]

I had a M25-5 with 0.455" chamber mouths and that pistol shot horribly with 0.452 commercial cast, better, but not stellar with 0.454" commercial cast. I don't think there is any way outside of reboring the barrel to 0.458" and shooting 0.458 diameter bullets will your revolver be accurate.

As for materials, that's a hard call. I want the maximum number of stress cycles before the cylinder cracks through fatigue. Since I don't know what exact materials S&W uses, I can't say which one is better, since cheap plain carbon steels would be inferior to a proper grade of stainless. I do believe that S&W would pick a low alloy carbon steel, maybe something better such as 4140, or 4340. What is needed in this application, once the strength is determined, is toughness.

If the pistol started out as blue steel, I think you might as well fit a blue steel cylinder. Just remember, these N frame pistols were using low pressure 45 LC rounds. Keep the pressures down, don't try to even get near 45LC + or +P+, and your revolver will shoot a hundred thousand round easily.

 

[Hair Trigger]

"Frankengun" it? Cylinders come on and off with the same ease as a set of stocks. The original cylinder will remain unused. It could even be argued that I'm preserving the original mal-formed cylinder by not using it and letting it develop a turn ring.

Beyond that, I could care less about affecting it's collector value. I am a shooter, not a collector. I intend this firearm to be the one I want, not to represent someone else's idea of what's appropriate.

It does have a pinned barrel. If it didn't I likely would not be looking into correcting this matter. SN seems to put it between 1980 and 1983. It's a later number so...likely more 1982-1983 if I were to speculate.

I'd actually love to be proven wrong, but with .458 bullets dropping freely through a couple of the cylinder holes, I think it's quite unlikely.

I wouldn't hesitate to modify a shooter grade gun to make it "better", but the way you described it, I assumed it was in above average condition and I don't consider any older S&W that's been modified from its original parts as being worth any more than a shooter grade gun regardless of its overall condition. I have a 4" M25-5 from 1980 and it has oversize throats, but it shoots as well as any other revolver I have, me being the limiting factor, and I'm not a terrible shot. It's nice enough that I wouldn't try to "fix" it if it didn't shoot well. It's your gun, do with it as you see fit.

 

[Doug M.]

It is not a collector item (which simply not a relevant consideration to me anyway) and the utility is likely decreased by the off sized cylinder. If it were mine, I would do the same thing, and being a mechanical dud, I would ship it to BMCM and pay his relatively low rates as an investment in getting it right.

 

[steelslaver]

I believe there is another factor that effects the guns with over sized throats. That is actual chamber size and brass size. Not only do throat sizes vary, but so do chamber sizes. When you couple ammo with brass a bit on the small size, with chambers a bit on the larges size with large throats you accuracy will suffer more than if one of those factors is removed. Throat size being the major. The closer the bullet is aligned to the bore from the get go the better. A slightly loose piece of ammo in a chamber will do better if the bullet is sitting in a proper throat. A loose piece sitting a bit low in a chamber where the throat allows the bullet to sit and start low is more apt to be inaccurate. Bullet shape and construction also being factors.

I would bet that a gun with over sized throats would be more accurate if the brass was left un sized, flared, then loaded and crimped. Trouble is that even if fired in the same gun, some of the rounds might not chamber. I know form checking with pin gauges that there are chamber and throat variations in each cylinder right out of the factory.

I also have 2 45 colt reamers and one is ever so slightly larger than the other.

 

[Shrek Of The Arctic]

Wulp...The results are in...sorta.

We just got our first snow of Winter in my part of Alaska, and it was mid teens today. Thus...the greatest inhibitor to acuracy had nothing to do with loose cylinder throats, and everything to do with the shaky nut behind the trigger. (AKA me) it was a bit uncomfortable today, and I have not shot anything more than .38 Special and the occasional .357 in a long minute. It was not a benchmark day.

Most importantly, My new Charter Arms did not even come close to hanging with the new to me 25-5. I would have been heartbroken otherwise.

Apparently, my 25-5 did not receive the memo that it's defective. It hung with my tried and true Mountain Gun every step of the way at 20 yards, mixed brass and all. They both shot groups that could be covered by the palm of my hand, which is the best I could have asked for with my shaky hands.

I am still proceeding with the purchase of a properly sized cylinder. Come Summer, it will just be good insurance if I take it out from 60-100 yards when I ain't shakin' like a leaf in the wind. I ran out of time to zero it, etc. But it could likely become my new nightstand gun once it is sighted in and I find/make some appropriate ammo.

 

[StrawHat]

…
Apparently, my 25-5 did not receive the memo that it's defective…

Yours is not the only one! I still have a Model 25-5 that shot very well with the .454" cast bullets I used at that time. Took quite a few deer with it.

Too many buy into the internet myth that ALL Model 25-5 shoot groups that can not be covered by my hat before they even shoot the revolver.

Glad to hear you decided to try it.

Kevin

 

[Shrek Of The Arctic]

I forgot to attach a couple pics. Truly exquisite? I dunno. It sure impressed this Arctic hillbilly who pretty much started on revolvers in his childhood due to the influence of one of these. As far as "original"? I dunno. Some ham fisted clown by the name of Hamilton Bowen already narrowed the trigger, tr, and hammer and worked the action over.

The top group was shot with my 625-9 Mountain Gun. Bottom group was the 25-5 in question. They seem...much more comparable than I expected.

We'll see how things shake out with steadier hands and warmer days, eventually.

 

[CH4]

Glad it shot better than you thought it would. You just don't know until you try.

 

[rays44]

Hamilton Bowen is one of the best and most respected gunsmiths in the country. I have one of his .50 Special conversions and would not describe his work as "ham fisted". Just my opinion.

 

[murphydog]

Hamilton Bowen is one of the best and most respected gunsmiths in the country. I have one of his .50 Special conversions and would not describe his work as "ham fisted". Just my opinion.

Suspect he may have been joking. Usually bad workers stay anonymous.

 

[BigMuddy]

I'm going to guess that maybe it was Hamilton who also changed out the front sight? Instead of the integral red ramp it has a pinned solid black sight. I wish my M25-5 had the same.

Before we had the internet the first "measurement" we used to make was group size. Glad to see yours shooting well.

Dan

 

[M29since14]

Hamilton Bowen is one of the best and most respected gunsmiths in the country. I have one of his .50 Special conversions and would not describe his work as "ham fisted". Just my opinion.

Concur. I'm pretty sure a tongue-in-cheek comment, too. If anyone knows a craftsman who does better work than Mr. Bowen I'd like to know about him. Hamilton is not only a master of his trade, he's also a very fine person all the way around.

I'm glad to know the gun shoots to your satisfaction up close. Would be interesting to know more about how it does at 50 yards. Good luck with your new .45.

 

[Shrek Of The Arctic]

I've long dreamed of owning a Hamilton Bowen revolver. Though this one is but a tiny demonstration of his work, it's still something I treasure. This gun is kinda like two bucket list items in one fell swoop.

I'll be mighty curious what 50 yards looks like as well. As pleased as I am for now, I don't think 20 yards tells the whole story, especially when fired from cold, shaky hands. I am awful thankful for positive signs and a good start though!

I neglected to mention the front sight base. I had to check the paperwork again to verify, but yes, the front sight was blessed by the touch of Mr. Hamilton as well. I can see this one making the occasional ASI or Steel Challenge and hanging out for night stand duty. My 625-9 Mountain Gun will remain my go to Alaska working gun.